1. Field of the Invention
The present invention relates generally to closable bags. More particularly, the invention concerns the method and apparatus for making a laminate to which spaced apart, elongated, matable metal strips are interconnected. Following construction of the laminate it is folded to create a tubular like construction which is sealed at either end to form a reclosable bag for containing food products and other articles.
2. Discussion of the Invention
In recent years, plastic bags have become very popular for use in the food industry to contain various types of food products such as chips, crackers, cookies, candy, coffee and the like. Frequently the bags are constructed from thin transparent sheets of cellophane and like materials. When the bags are to be printed, a laminate construction is often used with the printing being done on the inner surface of one of the two laminates. With this construction, the printing is viewed from the exposed side of the printed laminate with the printing ink being disposed against the inner wall of the second laminate. In this way, the printing ink is protected from damage and is prevented from coming in contact with the food articles contained within the bag.
Access to the articles within the bag is obtained by tearing the seal formed at the top of the bag and reaching into the article containing inner chamber. However, because of the inherent nature of the cellophane like material from which the bag is constructed, the bag having once been opened cannot easily be closed. If the user attempts to roll the top of the bag to close the opening, the memory in the cellophane like material will cause the bag to unroll once more exposing the articles contained there within. Because the reclosing problem is so aggravating and so frustrating, a number of clip like closure devices have been devised to clamp the folded opening of the bag so as to maintain the bag in a closed configuration. These clips are typically large, cumbersome and difficult to use and, in some instances, are simply not available.
The thrust of the present invention is directed toward the solution of the annoying problem of how to easily and effectively close cellophane-like bags after they have been opened. As will become better understood from the discussion which follows, the present invention solves this problem in an elegant manner by affixing thin lengths of longitudinally extending malleable metal strips to a thin film composite which is used to make up the side walls of the bag. These mallable metal strips enable the upper portion of the bag to be conveniently rolled upon itself in a manner to securely seal the opening therein.
In the past, it has been suggested that lengths of malleable wire be taped, or otherwise affixed to the walls of paper bags to enable the top portion of the bag to be rolled downwardly to close the top opening in the bag. However, the significant costs and difficulties associates with the large scale production of such bags has prevented them from coming into wide use. Further, because the wires and the tape which secured them to the walls of the bag were exposed to the interior of the bag, sanitation problems strongly mitigated against the use of such bags in the packaging of food products. Exemplary of such prior art constructions are those disclosed in U.S. Pat. No. 907,492, issued to T. T. Graser, U.S. Pat. No. 1,903,839, issued to T. M. Royal; U.S. Pat. No. 4,267,768 issued to Cieslak; U.S. Pat. No. 3,402,052 issued to Walker; U.S. Pat. No. 3,537,636 issued to Rochette; and U.S. Pat. No. 3,201,030 issued to S. Pollack.
The articles of the present invention and the methods and apparatus for their manufacture uniquely overcome the drawbacks of the prior art by providing, for the first time, state of the art, laminate bags suitable for a variety of uses, including use in the food industry. The reclosable bags of the invention are easily reclosable without the use of clips or other mechanical devices. Additionally, the novel methods of the invention, make possible the very large scale production of such bags at costs only slightly greater than the costs of laminate bags presently in wide use. Additionally, because in one form of the invention, the malleable wire or metal strips which uniquely permit reclosure of the bag are encapsulated between the laminates which made up the side walls of the bags, the articles contained within the bags can never come into contact with the bendable strips, thereby completely obviating the possible sanitation problems which plagued the prior art devices.
Because the present invention constitutes an improvement to the invention disclosed in U.S. Ser. No. 08/577,778, this latter application Ser. No. 08/577,778 is hereby incorporated by reference as though fully set forth herein.